U.S. patent number 5,350,388 [Application Number 07/893,109] was granted by the patent office on 1994-09-27 for hemostasis apparatus and method.
This patent grant is currently assigned to Albert Einstein College of Medicine of Yeshiva University. Invention is credited to Adam Epstein.
United States Patent |
5,350,388 |
Epstein |
September 27, 1994 |
Hemostasis apparatus and method
Abstract
A kit for effecting hemostatis of an organ comprises a mesh and
a sack. The mesh is formed of semirigid, bioabsorbable material
adapted to be generally conformingly disposed on at least the
bleeding surface of an organ. The sack is made of flexible,
elastic, air-impermeable material adapted to be elastically
stretched over the mesh and over a substantial portion of the organ
and then released to compress the organ portion and thereby
decrease the flow of blood thereto. The sack further permits
operative attachment of the undersurface thereof to a vacuum source
so that portions of the organ may be pulled outwardly by the vacuum
into the interstices of the underlying mesh to promote
hemostasis.
Inventors: |
Epstein; Adam (Brooklyn,
NY) |
Assignee: |
Albert Einstein College of Medicine
of Yeshiva University (Bronx, NY)
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Family
ID: |
26982253 |
Appl.
No.: |
07/893,109 |
Filed: |
June 3, 1992 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
Issue Date |
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708101 |
May 28, 1991 |
5186711 |
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320016 |
Mar 7, 1989 |
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Current U.S.
Class: |
606/154; 600/37;
606/151 |
Current CPC
Class: |
A61B
17/12 (20130101); A61F 2/0063 (20130101); A61B
90/00 (20160201); A61B 2090/0815 (20160201) |
Current International
Class: |
A61B
17/12 (20060101); A61B 19/00 (20060101); A61F
2/00 (20060101); A61F 002/00 () |
Field of
Search: |
;606/151,152,153,154
;623/11,12 ;600/37 |
References Cited
[Referenced By]
U.S. Patent Documents
Other References
Aglietti et al., "Traumatic Lesions of the Liver", Translation in
U.S. 07/708,101..
|
Primary Examiner: Rimell; Sam
Attorney, Agent or Firm: Amster, Rothstein &
Ebenstein
Parent Case Text
This is a divisional of copending application Ser. No. 07/708,101
filed on May 28, 1991, and now U.S. Pat. No. 5,186,711 itself a
continuation of Ser. No. 07/320,016 filed on Mar. 7, 1989, now
abandoned.
Claims
I claim:
1. Knit mesh for use in effecting hemostasis of an organ comprising
a mesh of semirigid bioabsorbable knit material defining two layers
inseparably knit together, each of said layers defining interstices
with an interstice of one layer communicating with a plurality of
only partially aligned interstices of the other layer.
2. Knit mesh for use in effecting hemostasis of an organ comprising
a mesh of semirigid bioabsorbable knit material defining two
inseparable layers, each of said layers defining interstices with
an interstice of one layer communicating with a plurality of only
partially aligned interstices of the other layer, the material
being knit in a rice point stitch.
3. Non-knit mesh for use in effecting hemostasis of an organ
comprising a perforated membrane formed of a thin semirigid
bioabsorbable, biocompatible non-knit material defining a plurality
of truncated, generally conical and spaced apertures wherein the
membrane is adapted to at least partially surround the organ.
4. The apparatus of claim 3 wherein the membrane surface to contact
the organ defines protuberances disposed about each of said
apertures and adapted to penetrate hard tissue of an organ.
5. The apparatus of claim 3 wherein said apertures are wider
adjacent the membrane surface to contact the organ and narrower
adjacent the membrane surface to be spaced from the organ.
6. The apparatus of claim 5 wherein said apertures are generally
truncated cones.
7. Non-knit mesh for use in effecting hemostasis of an organ
comprising a perforated membrane formed of a thin semirigid
bioabsorbable non-knit material defining a plurality of apertures
therethrough, said apertures being wider adjacent the membrane
surface to contact the organ and narrower adjacent the membrane
surface to be spaced from the organ, each of said apertures
defining teeth projecting inwardly toward the longitudinal axis of
said aperture and also toward said membrane surface to be spaced
from the organ.
8. A device for effecting hemostasis of an organ comprising:
(A) an air-permeable mesh of semirigid bioabsorbable material
defining interstices and adapted to be generally conformingly
disposed on at least the bleeding surface of an organ; and
(B) a sack defining a continuous surface made of flexible, elastic,
resilient air-impermeable material and an opening at one portion
thereof adapted to enable passage of the bleeding surface of the
organ therethrough, said elastic material being configured and
dimensioned to be elastically stretched over said mesh and over a
substantial portion of the organ and upon release to compress the
organ portion and thereby decrease the flow of blood thereto; said
sack further including means for the operative attachment of the
undersurface thereof to a vacuum source so that portions of the
organ may be pulled outwardly by the vacuum into the interstices of
said underlying mesh to promote hemostasis;
said mesh being a knit material defining two inseparable layers,
each of said layers defining interstices with an interstice of one
layer communicating with a plurality of only partially aligned
interstices of the other layer.
9. The device of claim 8 wherein said knit material is knit in a
rice point stitch.
10. A device for effecting hemostasis of an organ comprising:
(A) an air-permeable mesh of semirigid bioabsorbable material
defining interstices and adapted to be generally conformingly
disposed on at least the bleeding surface of an organ; and
(B) a sack defining a continuous surface made of flexible, elastic,
resilient air-impermeable material and an opening at one portion
thereof adapted to enable passage of the bleeding surface of the
organ therethrough, said elastic material being configured and
dimensioned to be elastically stretched over said mesh and over a
substantial portion of the organ and upon release to compress the
organ portion and thereby decrease the flow of blood thereto; said
sack further including means for the operative attachment of the
undersurface thereof to a vacuum source so that portions of the
organ may be pulled outwardly by the vacuum into the interstices of
said underlying mesh to promote hemostasis;
said mesh being a perforated membrane formed of a thin non-knit
material defining a plurality of interstices defining apertures
therethrough.
11. The apparatus of claim 10 wherein the membrane surface to
contact the organ defines protuberances disposed about said
apertures and adapted to penetrate hard tissue of an organ.
12. The apparatus of claim 10 wherein said apertures are wider
adjacent the membrane surface to contact the organ and narrower
adjacent the membrane surface to be spaced from the organ.
13. The apparatus of claim 12 wherein said apertures are generally
truncated cones.
14. The apparatus of claim 12 wherein each of said apertures
defines teeth projecting inwardly toward the longitudinal axis of
said aperture and also toward said membrane surface to be spaced
from the organ.
Description
BACKGROUND OF THE INVENTION
The present invention relates to apparatus and methods for
effecting hemostasis in an organ and, more particularly, to such
apparatus and method useful in effecting hemostasis in a
parenchymal organ such as the spleen or liver.
In an article entitled in English "Treatment Of Lesions of
Parenchymatous Organs--Original Technique" originally published in
Italy in 1986 under the title "Trattamento Delle Lesioni Degli
Organi Parenchimatosi--Technica Originale" Relazione 87.degree.
Congr. della Societa Italiana di Chirurgia--Torino 1986 and
abstracted in the Italian language publication Journal of Surgery,
Vol. VII, No. 3 (March, 1986), Aglietti et al. disclose a technique
for effecting hemostasis in a parenchymal organ such as the liver.
The disclosed technique involves the use of a bioabsorbable, flat,
single layer mesh which is manually conformed to the bleeding
surface of the liver and a suction-applying cup which is placed
over the mesh and the bleeding surface and manually maintained
there until homorrhaging terminates.
The Agletti mesh is formed of a bioabsorbable material such as
chromic catgut and is provided in rectangles or other shapes
approximately 5.times.10 cm in area. The mesh is woven in a plain
"left and right" weave and is therefore a flat monolayer. Typically
each square centimeter utilizes about 10 cm of thread and is 4-5
millimeter thick, each interstice of the mesh being about 2
mm.sup.2. The mesh provides a matrix of openings or interstices
through which portions or fingers of the bleeding surface may be
pulled, with the resulting infiltrating liver fingers being aligned
generally parallel to one another. The suction, vacuum or negative
pressure applied by the cup causes the parenchymal tissue to
infiltrate the interstices or openings of the gridlike weave of he
mesh. As soon as hemostasis is achieved, the cup is removed from
the mesh and the previously bleeding surface, with the mesh being
left imbedded in the parenchymal organ. In practice the Agletti
technique has not proven to be entirely satisfactory.
An important disadvantage of the Aglietti technique is the time
that must be wasted while the surgeon holds the suction cup over
the mesh of the bleeding surface until achievement of hemostasis.
The normally strong blood flow to the parenchymal organ supports
and extends hemorrhaging at bleeding surface by feeding additional
blood to that surface. Further, as the cup must be held in place by
the surgeon or his assistants until bleeding of the surface has
been effectively terminated (as evidenced by the end of blood flow
out of the cup), precious minutes may be wasted during which the
surgeon's attention might be profitably directed elsewhere,
especially where the trauma to the liver also affected other
organs. In some instances complete hemostasis is not achieved for
hours, and thus the patient must be left on the operating table for
a prolonged period of time.
A further disadvantage of the Aglietti technique is that the
portions of the parenchymal organ which infiltrate the interstices
of the mesh are in a parallel orientation to one another. While the
portions which have infiltrated and passed through to the other
side of the mesh typically expand and join to some degree on such
other side of the mesh, thereby promoting healing of the organ,
there is no positive mechanical influence biasing such portions
together so as to positively promote healing.
Accordingly, it is an object of the present invention to provide
apparatus which accelerates the effecting of hemostasis by
decreasing the blood flow to the organ being treated.
Another object is to provide such apparatus which positively
promotes the joinder of the organ portions infiltrating the
mesh.
A further object is to provide such apparatus which reduces or
eliminates the time during which the surgeon must manually maintain
the suction cup over the mesh on the bleeding surface.
It is also an object of the present invention to provide such
apparatus which, in one embodiment, permits the incision to be
closed and the patient removed from the operating table while
suction is still being applied to the bleeding surface and
mesh.
It is another object to provide a method of using such
apparatus.
SUMMARY OF THE INVENTION
It has now been found that the above and related objects of the
present invention are obtained by a device for effecting hemostasis
of the bleeding surface of an organ, especially a parenchymal organ
such as the spleen. The device contains a mesh and a sack. The mesh
is formed of semirigid, bioabsorbable material adapted to be
generally conformingly disposed on at least the bleeding surface of
the organ. The sack is made of flexible, elastic, air-impermeable
material configured and dimensioned to be elastically stretched
over the mesh and over a substantial portion of the organ and, upon
release, to compress the organ portion and thereby decrease the
flow of blood thereto. The sack further includes means for
operative attachment of the undersurface (i.e., inner surface)
thereof to a vacuum source, so that portions of the organ may be
pulled outwardly by the vacuum into the interstices of the
underlying mesh to promote hemostasis.
In a preferred embodiment, the mesh is made of a semirigid material
which is sufficiently rigid to preclude deformation under the
vacuum created by the vacuum source but sufficiently flexible to be
substantially conformed over the bleeding surface of the organ by
the sack. The mesh contains a plurality of interlocked layers, at
least some of one interstices of one layer being partially offset
from the interstices of an adjacent layer, whereby some portions of
the organ pulled outwardly by the vacuum into the interstices of
the mesh are also pulled at an angle to the thickness of the mesh,
thereby to promote joinder of some adjacent portions. Such a mesh
may have a rice point knit. The mesh may be substantially
coextensive with the sack, and preferably the sack and the mesh are
both bioabsorbable and joined together as outer and inner layers,
respectively, of a composite sack/mesh.
The sack, which may be made of bioabsorbable or non-bioabsorbable,
material is adapted to be elastically stretched and then released
to conform said mesh to the bleeding surface of the organ Upon
release, the sack effects an at least partially operative seal with
the organ about the bleeding surface thereof. The sack is made of
an elastic material which is sufficiently elastic to reduce the
size of the organ and thereby create a back pressure reducing or
terminating blood flow thereinto and to generally conform the mesh
to the outer surface of the organ.
The method of the present invention comprises the steps of applying
a mesh of semirigid bioabsorbable material to at least the bleeding
surface of an organ in generally conformingly disposition. Next a
sack made of flexible, elastic, air-impermeable material is
elastically stretched over the mesh and over a substantial portion
of the organ, and then the sack is released to compress the organ
portion and thereby decrease the flow of blood thereto. A vacuum is
then applied to the undersurface of the sack to pull portions of
the organ into the interstices of the underlying mesh to promote
hemostasis.
The present invention further encompasses the combination of a
mesh, a sack, a vacuum source, and means operatively attaching the
vacuum source and the sack so that portions of an organ are pulled
outwardly by the vacuum into the interstices of the underlying mesh
to promote hemostasis. The sack and the mesh are both bioabsorbable
and joined together as outer and inner layers, respectively, of a
composite sack/mesh so that the mesh and sack are applied together
as a unit to the organ. Preferably the vacuum source is disposed
outside of the body containing the organ, the combination
additionally including means for releasably securing the attaching
means and the sack, the releasable securing means being releasable
from outside the body.
The invention finally encompasses mesh for use in effecting
hemostasis of an organ. In one embodiment, the mesh comprises a
semirigid bioabsorbable knit material defining two inseparable
layers. Each of the layers defines interstices with an interstice
of one layer communicating with a plurality of only partially
aligned interstices of the other layer. The material may be knit in
a rice point stitch. In another embodiment the mesh is a perforated
membrane formed of a thin semirigid bioabsorbable non-knit material
defining a plurality of apertures therethrough. Preferably the
apertures are wider adjacent the membrane surface to contact the
organ and narrower adjacent the membrane surface to be spaced from
the organ, for example, generally truncated cones. Each of the
apertures may define teeth projecting inwardly toward the
longitudinal axis of the aperture and also toward the membrane
surface to be spaced from the organ. The membrane surface to
contact the organ may define protuberances disposed about the
apertures and adapted to penetrate hard tissue of an organ.
BRIEF DESCRIPTION OF THE DRAWING
The above brief description, as well as further objects and
features of the present invention, will be more fully understood by
reference to the following detailed description of the presently
preferred, albeit illustrative embodiments of the present
invention, when taken in conjunction with the accompanying drawing
wherein:
FIG. 1 is a fragmentary exploded front elevation view, partially in
section, of the mesh and sac about to be applied in turn to a
spleen, with a circled fragment of the sack being shown in a
greatly enlarged view;
FIG. 2 is a fragmentary front elevation view, partially in section,
of the mesh and sac applied to the spleen;
FIG. 3 is a fragmentary schematic vertical sectional view of the
mesh to a greatly enlarged scale;
FIG. 4 is a fragmentary top plan view of the mesh;
FIG. 5 is a front elevation view, partially in section, of a
preferred embodiment having a unitary mesh and sac about to be
applied to a fragmentarily illustrated spleen;
FIG. 6 is a fragmentary front elevation view, partially in section,
of the unitary sac/mesh applied to the spleen;
FIG. 7 is a fragmentary isometric view, partially in section,
showing the upper surface of an alternative mesh; and
FIG. 8 is a fragmentary isometric view, partially in section,
showing the lower surface of a variation of the alternative
mesh.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
Referring now to FIGS. 1 and 2, therein illustrated is a first
embodiment of the present invention comprising two separate
elements: a bioabsorbable mesh generally designated by the
reference numeral 10, and an elastic sack generally designated 12.
The device is adapted to be used in conjunction with a catheter 14
and a suction device (not shown) to effect hemostasis of an organ
generally designated 16, such as the spleen. It is contemplated
that the mesh 10 and sack 12 will be sold together as a unit,
optionally with the catheter 14. Typically the operating room where
the device will be employed will have its own suction device
available, but, if desired, particular kits may also include an
appropriate suction device.
According to the first embodiment of the present invention, the
mesh 10 is placed over the bleeding surface of the organ 16, and
preferably over the entire outer surface of the organ to
encapsulate the same, as illustrated in FIG. 2, and then the sack
12 is placed over the mesh 10 and over the entire outer surface of
the organ 16 or portion thereof to substantially encapsulate the
same. The catheter 14 provides fluid communication between the
inner surface 20 of the sack 12 and the vacuum source disposed
externally of the patient's body. The negative pressure between the
sack 12 and the organ tissue 16, applied through the mesh 10,
promotes incorporation or embedding of the mesh 10 within the organ
tissue 16 by drawing portions of the organ tissue 16 through the
interstices of the mesh 10. The infiltrating portions emerging from
the mesh 10 increase in volume by edema, thereby maintaining the
mesh 10 in place. Initially, the application of negative pressure
between the inner surface 20 of the sack 12 and the outer surface
22 of the organ tissue 16 (through the mesh) leads to collapse of
the blood vessels in the bleeding surface. The incorporation of the
organ tissue 16 within the mesh 10 tends to keep the collapsed
blood vessels of the tissue 16 in the collapsed condition.
Referring now to FIGS. 3 and 4, therein illustrated is a preferred
embodiment of the bioabsorbable mesh 10 of the present invention.
The mesh is preferably knit in a "rice point" stitch which provides
inseparable double layers 26, 28 of mesh, although a conventional
plain "left and right" stitch may be used instead. The "rice point"
stitch is also known as a "moss" or "seed" stitch (see M.
Dreiblatt, "Knitting for Everyone" (Doubleday & Co., Inc.,
Garden City, N.Y. 1964)). The resultant mesh is semirigid and
substantially non-stretchable. The stitches are very dense, each of
the interstices of the "rice point" mesh being approximately 1-9
mm.sup.2, so that the mesh contains about 50-70 stitches per
cm.sup.3. Each square centimeter of the "rice point" mesh requires
from about 15 to about 60 cms of thread, preferably about 30 cms of
thread. Each interstice or opening 30 of the "rice point" mesh is
joined with at least four other interstices 30 (only two of the
four being visible in the vertical section of FIG. 3) to provide a
three-dimensional structure having interstices which remains fairly
constant in size and resist in all dimensions either collapse or
enlargement due to traction, suction, pressure or stretching. On
the other hand, the mesh is sufficiently flexible so that it is
easily conformed to the surface of an organ by the finger pressure
of the surgeon or, as will be explained hereinafter, the pressure
exerted by a surrounding elastic sack 12. The semirigid nature of
the mesh renders it sufficiently rigid to preclude deformation
under the vacuum created by the vacuum source, as described
hereinafter, but sufficiently flexible to be substantially
conformed over the bleeding surface of the organ 16 by the sack 12,
as also described hereinafter.
A portion or finger 29 of the bleeding surface of the organ 16
infiltrating the interstices of the "rice point" mesh 10
(represented in FIG. 3 by an arrow) will, after an initial outward
extension through an interstice 30 of the first or inner layer 26
thereof, be diverted at an angle to the thickness of the mesh into
one of the four communicating adjoining interstices 30 of the
second or outer layer 28 which are at least partially laterally
displaced from the originally infiltrated interstice 30 of the
first layer 26. In the adjoining interstice 30 of the second layer
28, the finger 29 will be joined by other organ portions or fingers
29 which have infiltrated originally a different interstice 30 of
the first layer 26 and then been diverted to the same interstice 30
of the second layer 28. The close juxtaposition of the plurality of
fingers 29 within a single interstice of the second layer 28 (each
such finger 29 having initially infiltrated a different interstice
30 of the first layer 26) will promote their joinder and thus
healing of the organ 16.
In addition to its primary effect of promoting hemostasis of the
organ, as described above, the mesh 10 of the present invention may
serve two additional functions because it is preferably disposed
over the entire or substantially the entire portion of the organ 16
which will be covered by the sack 12, rather than merely the
bleeding surface of the organ. First, the mesh 10 acts as a
double-faced friction layer which, positioned intermediate the sack
12 and the organ 16, enables the inner surface 20 of the sack 12 to
be more securely retained on the otherwise very slippery,
blood-moistened outer surface 22 of the organ 16. The mesh 10
becomes embedded and fixed in the organ 16, and in turn provides a
secure surface for the sack 12 to grab frictionally. Second, once
the elastic sack 12 has compacted or reduced the size of the organ
16 (through its inwardly directed pressure and the resultant back
force on the flow of blood into the organ) and been removed from
the organ 16, the mesh 10 embedded in the organ 16 acts then to
maintain the organ in its compacted size and configuration. These
features are obtainable only where the organ portions 29
infiltrating the mesh 10 becomes securely locked therein, the same
occurring to a lesser extent with a conventional mesh and to a much
greater extent with a preferred mesh 10 according to the present
invention (for example, that made by the rice point weave or
another weave affording the same characteristics) where the change
of direction of the infiltrating portion 29 tends to lock it within
the mesh. These features are not totally obtainable with the
conventional woven mesh which tends to overly soften and become too
stretchable in the environment of the bleeding organ, and are fully
obtained only with the more resistant, non-stretchable, semirigid
preferred mesh of the present invention.
As the primary purpose of the sack 12 is to create a positive
inward pressure on the outer surface 22 of the organ 16 so as to
constrict and reduce the size of the organ 16 and thereby create a
back pressure which will lower or terminate the subsequent flow of
blood into the organ, the sack is constructed of an elastic
material. The sack may be of uniform elasticity throughout or may
have different levels of elasticity at different portions. For
example, where the sack is to cover a spleen, the stretchability of
the sack may be low at the area intended to cover the top of the
spleen, but should be higher at the open end and at the portions
which must be stretched to extend over the bulging sides of the
spleen. Similarly, the force generated by the material tending to
return it to its original configuration and dimensions is ideally
greatest immediately about the aperture thereof so that the
material about the aperture forms an effective air-tight seal with
the organ. Preferably the sack has a lip or rolled edge 34 about
its open end 36 both to reenforce the open end 36 (which typically
receives the maximum stretching) and to ensure formation of an
operative air-tight seal between the edge of the sack open end 36
and the organ 16 (see FIG. 2). The most desirable pressure for the
sack 12 to exert on an organ 16 or portion thereof will be a
function of that particular organ, and possibly even the portion
thereof. For example, the pressure of the blood within the spleen
is typically about 120 mm Hg. Thus, in order to substantially
reduce or terminate blood flow into the spleen, the sack should
exert a back pressure of about 80 to 130 mm Hg. Such a pressure on
the spleen typically results in a reduction in the volume of the
spleen of about 5-45%, frequently about 30%.
The sack may be fabricated in a variety of different configurations
so as to be suited for particular organs and, even more
specifically, for particular parts of particular organs. For
example, a sack intended to completely encapsulate a spleen 16
(except for the stem 38 containing the veins and arteries leading
into and out of the spleen) may have the configuration of a hollow
ellipsoid so as to enable it to completely cover the spleen 16
(except for the stem 38). On the other hand, a sack intended to
encapsulate a lode of the liver or a finger may have the
configuration of a hollow cylinder, closed at one end and open at
the other end. One skilled in the medical arts can easily determine
the appropriate sack configurations for other organs or organ
portions. Similarly, one skilled in the medical arts can easily
determine how much of a particular organ or portion thereof must be
covered or encapsulated if the sack is to remain in place on the
same, notwithstanding the elastic nature of the sack and the
possibly slippery nature and arcuated or irregular configuration of
the organ or portion thereof. The dimensions of the sack must, of
course, also be adapted to the particular organ or portions thereof
to be encapsulated.
Generally the sack effectively reduces the size of the organ and
creates a back pressure to diminish or terminate blood flow within
a period of seconds after it is applied about the organ. Preferably
the application of suction or negative pressure within the sack is
delayed until after the period of time required for blood flow
equilibrium to be achieved.
Furthermore, the sack 12 forces the mesh 10 to conform generally,
and in most instances very closely, to the outer surface of the
organ 16 in general and against any bleeding surface on the outer
surface 22 of the organ in particular. This minimizes the time
which a surgeon must take in order to carefully conform the mesh
over the bleeding surface, or over the organ as a whole, and
manually maintain it there until he begins suction.
A further advantage of the sack 12 is that it tends to force the
organ portions or fingers 29, which have infiltrated the mesh 10
from the inner surface thereof and which extend outwardly from the
outer surface thereof, into contact with adjacent portions 29,
thereby promoting embedding of the mesh 10 within the organ 16 and
joinder of the organ portions 29 on the outer surface of the mesh
so as to promote healing of the organ.
The present invention contemplates two different types of sacks 12,
one being bioabsorbable (like the mesh 10) and the other being
non-bioabsorbable. Within these constraints the sack 12 may be
formed of any material, whether natural or synthetic (such as
rubber, plastic, or the like), which provides the desired
elasticity and is biologically acceptable for use on the particular
organ.
Where the sack 12 is made of non-bioabsorbable material, it must be
removed from the interior of the body prior to closing of the
incision. Nonetheless, in addition to performing the functions of
reducing the blood flow to the organ and conforming the mesh to the
outer surface of the organ, the non-bioabsorbable sack provides a
convenient means for applying the suction or negative pressure to
the bleeding surface. Thus the surgeon or his assistants need not
manually maintain a suction or negative pressure device positioned
over the mesh until hemorrhaging is terminated, but are free to
devote themselves to seeing to the other injuries which may be
present in the surrounding areas and equally demanding of urgent
attention. Further, with the exception of the small tube or
catheter 14 which connects the sack to the suction device, the
general region about the organ is accessible to the surgeon and not
blocked either by the hands or devices otherwise required to
maintain a suction cup in position over the mesh.
Because a sack 12 promotes embedding of the mesh 10 within the
organ 16, even after the non-bioabsorbable sack 12 is removed from
the organ, the mesh 10 tends to retain the organ 16 in its
diminished size, thereby effecting a continued restriction of the
blood supply and lessening the chance of a recurrence of
bleeding.
The sack 12 is preferably made of bioabsorbable material because
the sack then, in addition to performing all of the functions noted
above with respect to the non-bioabsorbable sack, affords the
surgeon a greater range of options in treatment of the patient. At
a minimum, the surgeon does not have to take the time required to
carefully remove the sack 12 from the organ 16 without disturbing
the mesh 10. More importantly, the sack 12, until it is
bioabsorbed, continues support and reinforce the bioabsorbable mesh
10 which, depending upon the materials from which it is made and
the size of its individual threads or filaments, may otherwise
rapidly loose its mechanical strength once it is placed in the warm
moist environment of an organ. Indeed, all the surgeon must do
prior to closing of the incision is to remove the catheter 14 or
other means connecting the suction device to the inner surface 20
of the sack 12. In fact, as discussed hereinafter in connection
with the preferred embodiment of FIGS. 5 and 6, the incision may be
closed about the catheter 14 so that it is not even necessary to
remove the catheter 14 connecting the vacuum source and the sack 12
until long after the operation is completed.
Any conveniently available suction device capable of providing the
necessary negative pressure may be employed in connection with the
sack. A preferred suction device is an aspirator which enables the
blood removed from the bleeding surface of the organ to be
collected for immediate or delayed return to the patient.
A catheter or other flexible, hollow, air-tight tube 14 effects
fluid communication between the vacuum source disposed outside the
patient's body and the inner surface 20 of the sack 12 within the
patient's body. Preferably the suction device, the catheter, or the
sack is provided with a pressure regulating valve (not shown) to
limit any unexpected surge in negative pressure and enable the
surgeon to commence the negative pressure and adjust it to the
desired level.
The suction or negative pressure applied to the inner surface 20 of
the sack 12 should be sufficiently high that it effects the desired
embedding of the mesh 10 within the organ 16 (i.e., causes
infiltration of the interstices 30 of the mesh by the organ finger
portions 29, especially the organ finger portions of the bleeding
surface), but not so high as to cause injury to the uninjured outer
surface tissue of the organ. The appropriate pressure to be applied
will be a function of the type of organ, the type and extent of the
wound, and the like. For example, for the spleen, a negative
pressure of about 25 to about 30 mm Hg is preferred, although in
particular instances lower or higher negative pressures may be
usable. The negative pressure is applied until hemostasis is
achieved. While typically tamponade of the bleeding parenchyma of
the spleen is achieved within ten minutes, in particular instances
much greater periods of time (and even several hours) may be
required.
Depending upon the characteristics of the organ being treated, the
organ 16 may effect unintended seals with the sack 12 (i.e., other
than at the open end 36 of the sack) which have the effect of
leaving portions of the organ under the sack insulated from the
applied negative pressure. This potential problem may be dealt with
in a number of different ways. First, the inner surface 20 of the
sack may be provided with grooves 40, especially with fine grooves,
in a regular or irregular pattern to resist infiltration of the
grooves 40 by the organ 16, to communicate the negative pressure
over the entire inner surface 20 of the sack, and thus to equalize
the lower pressure around the organ. Second, a plurality of
catheters 14 may be used, each connecting the vacuum source (or
plurality of different vacuum sources) to different portions of the
inner surface 20 of the sack so that, even if the different
portions of the inner surface are not in fluid communication with
one another, each is nonetheless subjected to the same negative
pressure (or to different negative pressures where different air
sources are employed to provide different pressures to different
portions of the organ). Third, the sack itself may define
therewithin or thereon a network of fluid communication lines or
capillaries 42 which transmit the negative pressure from a central
point contacted by the catheter 14 to the more remote regions of
the inner surface 20 of the sack. In this instance the sidewall
portion of the catheter 14 passing through sack 12 will define
perforations communicating with the capillaries 42. Preferably one
of the capillaries 42 extends to the open end 36 of sack 12 and
therethrough at 42a to assist, by vacuum action, in drawing
together the open sack end 36 and organ 16 to effect the desired
pneumatic seal therebetween. Obviously, combinations of these
techniques may also be used.
In order to prevent the sack-penetrating end 44 of the catheter 14
from becoming clogged by the sack 12 itself, preferably either the
sack 12 is itself slightly rigid about the intersection of the
catheter 14 and the sack 12 or a stiffening collar 46,
substantially more rigid than the body of the sack 12, is disposed
about the sack-penetrating end 44 of the catheter 14 to distance
the more flexible material of the body of the sack 12 from the
catheter end 44. The collar 46 has an opening (not shown) aligned
with the catheter 14 to provide effective communication between the
catheter 14 and the organ outer surface 22 via the collar 46 and
mesh 10. The collar 46 may further be used to secure the catheter
end 44 to the sack 12.
To use the first embodiment, the mesh 10 is applied over the
bleeding surface of organ 16, and preferably also over the entire
organ outer surface 22. Then the sack 12, connected by catheter 14
to a vacuum source, is stretched around the mesh and around the
organ 16. Thereafter suction or negative pressure is applied via
catheter 14 until hemostasis is achieved. After hemostatis is
achieved, the sack 12, if non-bioabsorbable, is removed with
catheter 14 and the incision closed or, if bioabsorbable, is
separated from the catheter 14 which is then removed and the
incision closed.
Where the bleeding surface is not on the outer surface of the organ
but rather, for example, within a deep cut within the organ, in
addition to the mesh on the outer surface of the organ an
additional section of mesh may be manually inserted within the deep
incision and adjacent the bleeding surface.
As noted above, where the sack 12 is bioabsorbable, both it and the
mesh 10 may be left in place within the patient's body upon
completion of the operation, with the catheter 14 merely being
removed from the sack 12 prior to closing of the incision. Where
the catheter 14 is itself made of a bioabsorbable material, the
portion of the catheter protruding from the outer surface of the
sack 12 may simply be cut away, leaving whatever portion of the
catheter open end 44 is within or below the sack 12 to be
bioabsorbed over time with the mesh 10 and sack 12.
Referring now to FIGS. 5 and 6, therein illustrated is a second
embodiment to the present invention, generally designated by the
reference numeral 70, which differs from the first embodiment in
two major respects. First, instead of a separate mesh 10 and sack
12, there is a bioabsorbable composite mesh/sack, applied as a unit
to the organ and optionally left in the patient after the incision
is substantially closed. Second, the composite mesh/sack is
intended to be left in the patient's body with negative pressure or
vacuum still being applied to the organ until hemostasis is
achieved. As noted above, in certain instances bleeding does not
terminate rapidly and may in fact continue for hours, either
continuously or sporadically. In these instances, there are clear
advantages to a device which may be left in operating mode even
after the incision is substantially closed about the catheter which
connects the interior of the mesh/sack composite to the vacuum or
negative pressure source.
Elements of the second embodiment which are structurally identical
to elements of the first embodiment are identified by the
corresponding numerals, and those elements which are only
functionally similar are identified by the corresponding numerals
primed. Thus the mesh/sack composite 70 is comprised of an inner
mesh layer 10', an outer sack layer 12' and connected by a catheter
14' to a vacuum or negative pressure source 72 such as an
aspirator. The mesh 10' and sack 12' are both bioabsorbable and
substantially coextensive. Together they form composite structure
70 having the sack 12' as the outer layer and the mesh 10' as the
inner layer. A stiffening collar (not shown) may form an
intermediate non-coextensive layer positioned about the catheter
end. This second embodiment enables the mesh and sack elements to
be applied in a single motion over the organ 16, thus facilitating
and accelerating application of the device by the surgeon relative
to the time and effort required to sequentially position first the
mesh 10, and then the sack 12. Of course, where the bleeding
surface is disposed within the organ 16 rather than on its outer
surface 22, additional pieces of mesh 10 may be applied to the
bleeding surface as required.
In composite 70, the inner mesh layer 10' is secured to the outer
mesh layer 12.degree. only at points with excess material of inner
mesh layer 10' being provided between the points before the
composite is used. Thus, when the composite is used by stretching
it over an organ 16, the excess material of inner mesh layer 10'
enables the outer sack layer 12' to expand as necessary to fit over
the organ 16. Alternatively, although less desirably, the mesh
forming the inner layer 10' of the composite 70 may be more
stretchable than standard mesh 10 and secured to the outer sack
layer 12' uniformly at the interface between the two layers 10',
12', with the resultant composite 70 being able to stretch as
necessary over the organ.
In order to enable the catheter 14' to be removed from the
mesh/sack composite 70 once hemostatis is obtained, so that the
incision may be fully closed, the catheter end 44' is provided with
a surrounding elastic inflation collar 80 which is inflatable
either pneumatically or hydraulically by means of an inflation
catheter 82 connecting the inflation collar 80 to an inflation
source 84 through a valve 86 disposed outside of the patient's
body. Preferably the inflation collar 80 is a small inflatable
elastic balloon affixed to the end of the vacuum catheter 14' and
is hydraulically inflatable, and the inflation source 84 is a
reservoir, optionally pressurized, for saline solution or like
bioacceptable liquid for inflating the collar 80. While the
inflation catheter 82 connected to inflation source 84 is shown
separately from the vacuum catheter 14' connected to the vacuum or
negative pressure source 72, clearly one tube 82, 14' may be
inserted coaxially within the other tube 14', 82 for at least the
lengths of the tubes within the patient's body. While the inflation
collar 80 is shown as being disposed intermediate the inner surface
of the outer sack layer 12' and the outer surface of the inner mesh
layer 10', if desired either layer 10', 12' or the optional
stiffening collar could be provided with appropriate recesses (not
shown) to receive the inflated inflation collar 80 and maintain it
in position as long as it is inflated.
When the inflation collar 80 is inflated by the inflation liquid
from inflation source 84 via inflation catheter 82, it enters into
an appropriate recess to releasably secure catheter end 44' to the
composite 70 and preclude its withdrawal. During the operation the
inflation collar 80 is maintained in its inflated state by closing
of the valve 86 and thus closing of the inflation tube 82. After
the operation is completed and the incision is closed about the
tubes 82, 14', suction or negative pressure continues to be applied
to the composite 70 from the negative pressure or vacuum source 72
via catheter 14' either continuously or intermittently as needed
(for example, whenever bleeding resumes as evidenced by the
appearance of blood in the aspirator 72), when permanent hemostasis
is achieved, it is only necessary to open the valve 86 from outside
the patient's body, at which point the stretched outer sack layer
12' will force the inflation liquid from inflation collar 80 back
out through inflation catheter 82 and valve 86 into the inflation
source 84, thereby allowing the inflation collar 80 to collapse.
Once the inflation collar 80 is collapsed, both tubes 82 and 14'
are then easily withdrawn from the composite 70 and removed from
the patient's body, whereby the surgeon has only to complete
closure of the incision.
Prior to use the composite 70 may be compactly and conveniently
rolled up, as illustrated in FIG. 5, in the manner of a condom
ready to be applied to the organ.
It will be appreciated that the composite mesh/sack construction 70
may be employed with a non-releasable catheter 14 (as in the first
embodiment) which is not releasable from the composite 70 from
outside the patient's body where it is intended that the catheter
will be removed at the conclusion of the operation.
To use the second embodiment, the center point of the composite 70
is applied to the organ 16 and the rolled up edges are unrolled and
stretched around the organ outer surface 22 as a unit. Suction or
negative pressure is applied intermediate the sack outer layer 12'
and the organ outer surface 22. The catheter 14' may be in place
during application of the composite 70 on the organ 16 or may be
inserted after the composite 70 is in place. In either case, once
the catheter 14' is appropriately positioned with its inflation
collar 80 adjacent an appropriate recess of the composite 70, valve
86 is opened to permit the inflation source 84 to inflate the
collar 80 via inflation catheter 82, after which the valve 86 is
closed. The incision may then be closed about the catheters 14', 82
with negative pressure still being applied to catheter 14'. When
hemostasis is achieved, valve 86 may be opened, thereby permitting
collapse of the inflation collar 80 and thus withdrawal of the
suction catheter 14' (including inflation collar 80) and inflation
catheter 82 from the composite 70. Only the relatively small
portion of the incision left open for passage of the catheters 82,
14' need then be sutured.
The term "mesh" is employed in its broad sense of something that
snares or entraps. While the mesh 10, 10' described hereinabove is
preferably a knit material, and more particularly a material which
has been knitted in a "rice point" stitch, non-knitted materials
may be used in the present invention as well. For example,
referring now to FIG. 7, a perforated non-knit membrane 90 may also
be used as the mesh 10, 10'. The membrane 90 comprises a thin
bioabsorbable semirigid material 91 (about 3-7 mm thick) defining a
plurality of apertures 92 extending therethrough. While the
apertures 92 may be cylindrical in configuration, they are
preferably generally conical, with the inner surface of the mesh
adapted to contact the organ being the broader base (about 3-6 trim
in diameter) and the truncated tip or top of the cone (about 1-3 mm
in diameter) being the outer surface of the mesh adapted to contact
the sack. A preferred separation between adjacent conical bases is
about 1-4 mm so that there are about 1-6 apertures per
cm.sup.2.
Each aperture 92--whether or not conical in
configuration--preferably defines one or more teeth 94 which extend
inwardly towards the longitudinal axis of the aperture 92 to engage
any organ portions or fingers 29 (represented by phantom arrows in
FIG. 7) which enter into the aperture 92. There may be a plurality
of rows of teeth 94, and the teeth 94 may abut adjacent teeth 94 to
form a continuous ring or inward projection of the aperture 92. The
teeth 94 may extend perpendicular to the longitudinal axis of the
aperture 92, but preferably extend at an upward angle thereto
(toward the organ-contacting end of the axis) to facilitate entry
of the organ fingers 29 thereinto and by engagement therewith
enhance retention of the organ fingers 29 within the aperture
92.
In instances where the injury is rather deep and not merely a
surface injury, the mesh may desirably be formed by two or more of
the perforated membranes 90 disposed one on top of the other
(preferably with a slight separation of about 3 mm therebetween) or
a single perforated membrane of more than the usual thickness and
defining two or more at least partially longitudinally aligned and
communicating half-apertures 92, each having optionally its own
unique shape and teeth.
The mesh of membrane 90 is utilized in the same member as the mesh
10, 10' with two additional advantages. First, the drawing of the
tissue fingers 29 through the conical apertures 92 from the broad
base through the truncated top causes the tissue fingers 29 to
initially decrease in volume (and thereby further collapse the
blood vessels therein) and then expand as a result of edema as they
emerge from the aperture 92. Second, the teeth 94 trap the tissue
fingers 29, thereby preventing a retreat thereof and insuring
secure imbedding of the membrane 90 within the organ 16. Neither of
these beneficial effects are obtained in the knit mesh 10, 10'
where the interstices are cylindrical and devoid of teeth.
Referring now to FIG. 8, where the membrane 90 will be employed for
effecting hemostasis in hard tissue (such as kidney and muscle
tissue) as opposed to soft tissue (such as liver and spleen
tissue), the organ-contacting surface of the membrane 90 may be
provided with protuberances 96 adapted to facilitate penetration of
the hard tissue of the organ 16 and thereby promote embedding of
the mesh 90 within the tissue. The protuberances 96 are preferably
pyramidic in shape with the points pointing in the direction of the
organ 16 so that, as the membrane 90 is placed over the organ 16,
the points of the pyramids 96 penetrate the hard tissue of the
organ 16. The protuberances may be 2-8 mm in height with each side
of the base being about 1-4 mm. If desired, teeth 98 may also be
provided on the protuberances to further facilitate engagement of
the tissue by the protuberances 96, the teeth 98 extending
outwardly from the protuberances and preferably towards the base
thereof. The protuberances 96 are preferably disposed about the
periphery of the broad base of the conical apertures 92 in such a
manner as to not interfere with the communication of suction
through the apertures 92. For example, each broad base of a conical
aperture 92 may be surrounded by the bases of four pyramids 96.
Clearly the preferred meshes 10, 90 of the present invention, while
intended for use in connection with the sack 12 of the present
invention (whether the sack 12 is a separate element or a composite
therewith), will also find utility in conventional suction
techniques for effecting hemostasis, such as the aforementioned
techniques expounded by Dr. Aglietti which did not utilize a
sack.
Any reference herein to the sack or mesh covering or encapsulating
an organ, as used herein, does not imply 100% encapsulation of the
organ, but rather allows for interruption of the sack or mesh for a
stem or similar portion containing veins and arteries connecting
the organ to other portions of the body.
Now that the preferred embodiments of the present invention have
been shown and described in detail, various modifications and
improvements thereon will become readily apparent to those skilled
in the art. Accordingly, the appended claims should be construed
broadly, and in a manner consistent with the spirit and scope of
the invention herein.
* * * * *